Hydrolysates, chromatograms

Fig. 2.71. HPLC chromatogram of the neutral (a) and acidic fractions (b) and the acid-catalysed hydrolysed product of freshly squeezed cranberry juice (c) at 280 nnm. Peaks in a 1 = ( + )-cate-chin 2 = myicetin 3 = quercetin (added as internal standard). Peaks in b 1 = anthocyanin derivative I 2 = benzoic acid 3 = p-anisic acid 4 = quercetin (added as internal standard). Peaks in c 1 = ( + )-catechin 2 = anthocyanin derivative I 3 = anthocyanin derivative II 4 = benzoic acid 5 = anthocyanin derivative III 6 = p-anisic acid 7 = myricetin 8 = quercetin. Reprinted with permission from H. Chen et al. [188].

A different HPLC system was developed for the monitoring of anaerobic azo dye degradation. The scheme of the system is shown in Fig. 3.96. The HPLC system was similar to that described in ref. [155], A chromatogram illustrating the separation of the hydrolysed azo dye Reactive black 5 (RB5-H) and its decomposition products is shown in Fig. 3.97. This monitoring technique has also been proposed for the screening of the performance of bioreactors by measuring the composition of waste-water [156],... 

Fig. 3.124. Chromatograms of a 1 1 dye mixture (a) 40 min before addition of Na2C03, (b) 10 min after addition of Na2C03, and (c) 60 min after addition of Na2C03 flow rate = 0.6 ml/min, other conditions are described in the text. The peak at 4.57 min in (a) and the same peak (smaller in size) at 4.54 min in (b) are both attributed to the functional group of cibacron yellow ( — F) the peak at 7.54 min in (a) and the same peak (smaller in size) at 7.40 min in (b) are both attributed to the hydrolysed part of the functional group of cibacron yellow the peaks at 5.07 min in (b) and 5.22 min in (c) are attributed to the hydrolysed part of the functional group of cibacron blue. Reprinted with permission from A. Zotou et al. [175].

Fig. 3.134. Chromatogram of the synthesized hydrolysed dye and parent dye in buffer of pH 11 recorded after various times of hydrolysis at 90°C (a) synthesized hydrolysed dye, (b) 0 min, (c) 10 min, (d) 20 min, (e) 30 min, (f) 40 min where components P and H represent parent dye and hydrolysed dye. Reprinted with permission from J. Koh et al. [180].

The chromatogram of free BA standard mixture is reported in Fig. 5.4.7. The Br-AMN degradation products are eluted at lower retention times than derivatised BA, close to the solvent front, so they do not impair BA separation. Free BA fraction also encloses taurine conjugates, previously enzymatically hydrolysed. The separation of glycine conjugated BA is illustrated in Fig. 5.4.8. In both chromatograms, the peaks of BA naphthacyl esters are fully resolved and separated from the reagent peaks. 

Period 2 Part B—Work up the dansyl hydrolysate and spot on the TLC plate with standard dansyl amino acids. Part A. 1—Work up peptide hydrolysate and prepare FMOC derivatives of amino acids for analysis by HPLC or CE. Part A.2-If applicable, develop paper chromatogram in solvent system. 

For the study of soluble polysaccharides, a treatment with diluted TFA is sufficient and the reaction time can be kept short (7). Soluble polysaccharides of wood are separated from holocellulose by extraction with alkali. Wise et al. (10) term the extract with 5% KOH polyoses (hemicelluloses) A. Polyoses A can be hydrolyzed completely with 2N TFA within 1 hr. The chromatograms of the hydrolysates of polyoses A from spruce and beech holocelluloses recorded with a sugar analyzer (Biotronik ZA 5100) are shown in Figure 1. 

Figure I. Chromatograms of the hydrolysates of polyoses A from spruce-wood and beechwooa. Rha = rhamnose, Man = mannose, Ara = arahi-nose, Gal = galactose, Xyl = xylose, M-GluU = 4-O-methylglucuronic...

In Figure 2 the chromatograms of the hydrolysates of wheaten bran, draff, and pease-meal are presented these substances can be hydrolyzed easily with 2N TFA in 1 hr. 

Figure 2. Chromatograms of hydrolysates of wheaten bran, draff, and...

The whole procedure normally takes about 1 hr. The acid is then evaporated, and the dry matter can be analyzed. This method can be applied to cellulose from wood, as a-cellulose or pulp, or to other celluloses (e.g., cotton) as well as to cellulosic materials with higher amounts of other polysaccharides (e.g., holocellulose). The chromatograms of the hydrolysates of a-cellulose from beechwood and of holocellulose from sprucewood (Figure 6) are examples of the application of this method. Compared with sulfuric acid hydrolysis, the total sugar yield from the spruce holocellulose is higher after the hydrolysis with concentrated TFA (Table II). Regarding the individual sugars, it can be seen that the... 

Figure 6. Chromatograms of the hydrolysates of a-cellulose from beech-wood and holocellulose from sprucewood...

Comparison of the chromatograms of the hydrolysates of ashwood after the intensive and more... 

Figure 8. Chromatograms of the hydrolysates of materials with low polysaccharide content milled wood lignin (MWL) from sprucewood and a 180-million-year-old protopinacea...

Figure 10. Liquid chromatogram of hydrolysate from action of cellobiohydrolase on Avicel...

Figure 6.15 presents the LC-UV chromatogram of the hydrolysis products from the first step of simulated waste water treatment of Remazol Black 5 (RB5), a commercially important textile dye, while Figure 6.16 shows a series of stop-flow LC-NMR spectra acquired in an LC-NMR-MS run. The NMR and MS data of the tentatively identified compounds are shown in Tables 6.6 and 6.7, respectively. These are only by- or degradation products which elute earlier than the hydrolysed Remazol Black. Peaks which elute later consist of coeluting dye components which have not yet been identified. 

Our first separation method involved running the simultaneous steam distillation extraction under 100 mm vacuum in order to minimize heat effects. This was followed by extraction under atmospheric pressure in order to get more complete recovery. This atmospheric extraction was run for 10 days, using a fresh hatch of solvent each day (68-69). Approximately 10 times as much material was collected each day at atmospheric pressure as was collected under vacuum. Since Schultz, et. al. (70) showed that many non-water-soluble alcohols, esters, aldehydes, and ketones can he recovered by this system in less than 3 hours, the collection of a large amount of material after 10 days is indicative of a very complex and probably dynamic system. Gas chromatograms for these extracts (68.) and some compound identifications (69.) have been reported. (Other reports on the identification of volatiles from protein hydrolysates are given In references 71-75). Prelminary results have shown that the vacuum extracts are more attractive for the Medfly than the atmospheric ones. 

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